With the development of technology, personal consumer electronics, such as smart phones, are more and more powerful in functions. Although the smart phone can provide people with more convenience and choices, it also has to provide a battery with a larger capacity. Otherwise the battery carried by the mobile phone is easy to run out, and cannot provide enough endurance, for which reason a rechargeable battery capable of charging the battery in emergencies is needed.
The existing power supply is usually separated from the mobile phone, the power supply is connected to the mobile phone, so that it is inconvenient for the user to carry. At the same time, the appearance of the smart phone is more and more delicate, the electronic components are also more and more elaborate, and its function is more and more powerful. During use, the user prevents the smart phone casing from being scratched and reduces the influence of the external force on the performance of the smart phone, so the smart phone usually has to be provided with a protective sleeve. Since the smart phone protective sleeve does not have a power supply, the smart phone cannot be charged. Meanwhile, the mobile power supply or standby power supply often fails to protect the smart phone, and the connection has to be made through a connecting wire when the mobile power supply or the standby power supply is used, so that it is inconvenient to use and carry.